It would be easy to come away from Elena Kagan's confirmation hearing with the impression that, in the minds of some senators, certain members of the Supreme Court might be -- how to put this? -- less than truthful.

Or, at least, dissemblers. The Senate Judiciary Committee's 17-hour, 500-question grilling of the Supreme Court nominee was marked by repeated references from some senators to feeling burned by the three previous nominees: John G. Roberts Jr., Samuel A. Alito Jr. and Sonia Sotomayor.

"You know, we've become skeptical," Sen. Tom Coburn (R-Okla.) told Kagan, because "it really isn't going to matter what you said, because once you're there, you're there, and we have very little ability to change it."

Coburn was criticizing Sotomayor at the time, saying her vote in a recent gun rights case was at odds with her testimony before the committee just a year ago. But he acknowledged his Democratic colleagues' similar critiques of Roberts and Alito, who were nominated in 2005.

"You can understand the skepticism we might have, and especially in the fact that many on the other side of the aisle, the implication has been that the same thing by Alito and Roberts, that they weren't straightforward, that, in fact, they didn't keep their word on stare decisis," Coburn said, referring to the principle of respecting the court's precedents.

But some believe the fault is with the Senate and the process. While senators all say they realize it is improper to ask how a nominee will vote on a specific case, they press for the nominee's "personal" view, how the nominee would vote on a case just like the one in question or whether the nominee pledges loyalty to a precedent.

Nominees try nuance; senators hear reassurance.

"The answers that nominees give are very much like clauses of the Constitution," said John Anthony Maltese, a political scientist at the University of Georgia. "Different people read different things into them."

Benjamin Wittes, who has studied and written about the nomination process, argues that the very act of trying to determine what a nominee will do on the court -- rather than simply whether she is qualified to serve -- is wrongheaded, a result of senators decades ago trying to determine future justices' positions on segregation.

It is a process "born in original sin, born in impropriety and has never risen above it," said Wittes, a scholar at the Brookings Institution. "The nominee only has one defense against it, which is to not answer."

But they do, in some fashion, and senators say they should be able to hold nominees to their word. Roberts, for instance, told the committee that it is a "jolt to the legal system when you overrule a precedent."

But the court he leads has done just that several times. In the most controversial example, Roberts was part of a five-member majority in Citizens United v. Federal Election Commission that cast off two precedents and struck decades-old prohibitions on the role of corporations in campaigns.

Roberts wrote a 14-page concurrence in the case, joined by Alito, to explain his position. But Sen. Arlen Specter (D-Pa.) referred to the document as "an apologia, really a repudiation of everything he testified to, just diametrically opposed." Specter put into the record his questioning of Roberts five years ago.

"I again acknowledge it's a big difference between appearing here at a nomination proceeding as opposed to deciding a case in controversy," Specter said. "And I don't challenge Chief Justice Roberts's good faith, but it does leave us perplexed as to where we're at."

Sen. John Cornyn (R-Tex.) said he was just as frustrated with Sotomayor. She said at her hearing last year that she considered as "settled law" the court's 2008 decision in District of Columbia v. Heller, which established for the first time that the Second Amendment provided an individual right to gun ownership.

But in Monday's decision in McDonald v. Chicago, Sotomayor sided with the dissenters and did not find that the Second Amendment applied to state and local efforts to restrict guns. "It is disconcerting . . . and in fairness, does appear to be a direct contradiction of what Judge Sotomayor said in her confirmation hearings with what she has decided on the first opportunity to decide a case on that same subject," Cornyn said.

Sen. Jeff Sessions (R-Ala.) tried to pin Kagan down on whether a certain case she, too, declared "settled law" meant that she would be a supporter if the controversy arose again.

"Senator Sessions, it wouldn't be appropriate for me to bind myself with respect to any future case that came before me," Kagan said. "It wouldn't be appropriate for me in any case to say, 'Oh, I promise that I'm going to take a case like that and do, you know, X, Y, Z with it.' "

"Well, I think that's what I expected," Sessions said. "I think you'll go to the court free to vote either way on any of those cases, and we should fully understand it."

Donald B. Ayer, a former deputy attorney general who has a private appellate practice, wrote an opinion piece in The Washington Post before the hearings began, criticizing the process. After the proceedings, he said he thought that the committee came away with a good view of Kagan's expertise and qualifications for the job, even if she offered few specifics on her views.

He said the senators should be glad when they see evidence that justices have taken positions different from what might be expected, because it shows they have taken seriously their oaths to judge each case individually.

In the term just completed, for instance, he said liberals should like that Roberts separated himself from fellow conservatives and voted that it is unconstitutional in some cases to sentence juveniles who have not killed to life in prison without parole. Similarly, conservatives should be heartened that retiring Justice John Paul Stevens, leader of the court's liberal wing, voted with conservatives to uphold a statute forbidding groups from providing even humanitarian advice to groups designated as foreign terrorists.

"You shouldn't expect nominees to lock themselves into specific views; they tell you they're not going to do that, they refuse to do that," Ayer said. "I don't think there's any basis in saying they're acting in bad faith later."